Engine cylinder block wall reboring implement



July 20, 1 937.

F. svAB A 2,087,823 ENGINE CYLINDER BLOCK WALL REBORING IMPLEMENT FiledJuly 19, 1955 2 sheet-sneet 1 /0 2s Q M ff 1 r:- 2a Q l 1 Q i K (j/6,6.

si 1 Q Q lj /z Agg" Inventor 1` YI/a l 'A I ByQ/lnwoml i: 2,4 I

A Homey July zo, 1937. E. F.' sv-AB 2,087,823

ENGINE CYLINDER BLOCK WALL REBORING IMPLEMENT Filed July 19, 1935 2sneetsfsheet 2 Inventor Lay/@mmm Attorney l v Patented July 20, 1937 vENGINE CYLINDER BLOCK WALL REBOR- ING IMPLEMENT Edward F. Svab, Hudson,Ohio y Application July 19, 1935, Serial vNo. .32,301V

l Claim.

This invention relates to a cylinder block wall reboring implement forengines.

The primary object of the invention is a novel design of an implement ofthe character referred to that permits very light construction so thatit is light to handle, convenient to manipulate and easy to adjust.

A further object of the invention is to provide an implement of thecharacter referred to that allowsthe cylinderblock of an engine to berebored without removing the cylinder block from the chassis of anautomobile.

Further objects of the invention are to provide a device of thecharacter referred to that accommodates a change of one size to -anotherin a comparatively short time, that does not require the walls of thecylinder to be polished after the reboring operation, that is highlyeiicient for its intended purpose and comparatively inexpensive tomanufacture and operate.

With the foregoing and other objects in view the invention consists inthe novel construction, combination and arrangement of parts as will behereinafter more specifically described and illustrated in theaccompanying drawings wherein is disclosed an embodiment of theinvention, but it is to be understood that changes, variations, andmodifications may be resorted to without departing from the spirit ofthe claim hereto appended:

In the drawings wherein like reference characters denote correspondingparts throughout the several views:

Figure 1 is a top plan view of the reboring implement constructed inaccordance with the present invention.

Figure 2 is an end view at the upper end thereof.

Figure 3 is a diametric sectional view taken substantially on line 3-3of Figure 1.

Figure 4 is a diametric detailed sectional view taken substantially online 4 4 of Figure 1 and looking in the direction of the arrows.

Figure 5 is an enlarged perspective View of the upper end of the mandrelwith parts thereof removed.

Figure 6 is a fragmentary perspective view of an end of one of thestabilizing blocks.

Figure '7 is a perspective fragmentary View of the blade.

Referring to the drawings in detail IU indicates generally a hollowcylindrical mandrel of uniform diameter and open at each end. It will benoted as the description proceeds that the construction of the implementadmits of a Very light implement easy to handle and well balanced, andin keeping with this purpose the thickness offthe walls of the mandrelare considerably reduced, from the customary practice; The length ofthemandrel from one end to the other-should be such as will be slightlylonger than the cylinder blocks used in internal combustion engines forautomobiles. There is a blade receiving slot I I in the mandrel whichextends from a point adjacent one end thereof to a point adjacent theother end thereof. The slot I I extends throughout the major portion ofthe mandrel. Thereare a pair of spaced longitudinally extending 'supportbars I2, I3 secured by the screws I4 tothe outer face of the mandrel oneto each side of the slot. The space between the confronting faces of thesupport bars registers with the slot I I. The bars I2, I3 aresubstantially coextensive with the length of the slot and theconfronting edges I5, I6 respectively of the bars are parallel anddisposed on a bias with respect to the diameter of the mandrel. Thespace between the confronting edges of the bars forms a tight slidingfit with the opposed faces of the blade as will herein-after c appear.The heads of the screws I4 are countersunk with respect to the outerfaces of the bars. The blade II is an elongated bar which seats edgewisein the space between the supporting barsL I2,v I3 and the inner endthereof extends into the slot II so that the blade may be adjustedradially as will hereafter appear. The slant of the blade is in adirection away from the travel of the mandrel and the cutting edge I8thereof is along the corner of the blade. The trailing portion of theblade is provided with the usual clearance.

Longitudinally extending stabilizing blocks I9, 20 are secured to theouter face of the mandrel by means of screws 2| the heads of which arecountersunk in the outer face of the blocks. The blocks I9, 20 extendthe major portion of the length of the mandrel l0 and arecircumferentially spaced at points substantially equidistant from theblade support and from each other. The outer surface of the blocks arerounded so that when they rub the wall of the cylinder being reboredthey will not injure the same.

Reinforcing rings 2I, 22 are secured inside of the mandrel by means ofthe screws 23 one adjacent each end of the mandrel. The reinforcingrings are positioned so that the ends of the blades bear on the majorportion of the outer periphery. In each reinforcing ring there is aradially supported set screw 24 the head of which extends into theinterior of the mandrel and the end of the shank bears against the inneredge invention the end of the mandrel away from the handle 26 isinserted in the top of the cylinder first. The blade Il should then beadjusted by the set screw 24 until they touch the walls of the cylinderto be rebored. When the blade has A been adjusted to touch the wall themandrel is turned in a clockwise direction with respect to Figure 2 bythe handle 26. It has been found by experience that the blade shouldnever be ex-y tended above the face of the supporting blocks beyond onequarter of an inch.` If it is necessary to extend the blade further thanone quarter of ari-inch it is necessary to change the stabilizing blocks19, 20 and apply thicker or higher blocks. In other words, in reboringcylinders customarily used in automobile engines the height of thestabilizing block should never allow any greater clearance between theblocks and the cutting edge I8 of the blade of more than one-quarter ofan inch. l

When the end of the mandrel is inserted to a point where the bladebegins to resurface the cylinder the construction of the implement inaccordance With the present invention requires very little downwardpressure beside the turning of the mandrel. It has been found that theturning of the mandrel will cause the same to progressively move axiallyof the cylinder under its own weight.

Having described my invention, what I claim is:

A manually operated cylinder block reboring implement comprising anelongated sleeve mandrel equipped with a continuous slot extendingthrough the wall and in an axial direction along the major portion ofthe length intermediate the ends of said sleeve, a pair of elongated,As/paced blade supporting bars, of a length substantially equal to thelength of the slot, said barsbeing secured to the outer periphery of thesleeve one on each side of the slot and having the space therebetweenregistering with said slot, the confronting edges of the bars beingparallel and disposed at an angle relative to the diametric plane of thesleeve passing through the slot, an elongated blade of a lengthsubstantially equal to the length o1" the slot and seated edgewisetherein, said blade extending outwardly from the slots through saidspace and having a tight sliding fit between the confronting edges ofthe supporting bars, reinforcing members' inside the sleeve, radiallydisposed adjusting screws carried by the reinforcing members and havingtheir outer ends bearing against the blade to adjustably support saidblade, and spaced stabilizing blocks mounted on the periphery of thesleeve in spaced relation to the supporting bars.

EDWARD F. SVAB.

